textproduct: Albany

WHAT HAS CHANGED

Increasing confidence for accumulating snow late Friday into early Saturday morning, with the greatest potential along and south of I-90.

KEY MESSAGES

1. Locally slippery travel conditions through early this morning, mainly across the western Adirondacks and southern Greens in VT where snow showers will end this morning.

2. Strong gusty west/northwest winds develop late early this morning and persist through late morning, with gusts reaching 40-50 mph within portions of the Mohawk Valley, Capital District, eastern Catskills, Berkshires and central/northern Taconics.

3. Accumulating snow expected late Friday into early Saturday morning, with the most impactful snowfall mainly near and south of I-90.

4. Precipitation develops Sunday and may continue into Monday morning, likely beginning as snow or a wintry mix (including freezing rain) before potentially ending as plain rain.

DISCUSSION

KEY MESSAGE 1...

Radar, obs and webcams indicating snow showers across mainly higher terrain areas in the W/S Adirondacks and S. Greens, mainly driven by upslope along with a short wave trough moving through. Isolated to scattered rain/snow showers occurring in lower elevations and along the surface cold front moving east across the region. So will keep the Winter Weather Advisory going for the W/S Adirondacks, W. Mohawk Valley and S. Greens through 7 AM today. Temperatures are mainly in the mid 30s in lower elevations and lower 30s in the mountains early this morning. Snow showers will gradually end this morning as surface high pressure starts to build in from the west.

KEY MESSAGE 2...

Winds will shift to the west-northwest behind the cold front starting before sunrise today. Cold advection will promote decent mixing, with fairly strong winds at the top of the mixed layer also enhanced by channeling down the Mohawk Valley, Capital District into the Berkshires. Still expecting maximum gusts of 40-50 mph in the Wind Advisory area. Winds will decrease below advisory criteria by this afternoon, but remain gusty through the daylight hours.

KEY MESSAGE 3...

After a fairly quiet period Christmas Day outside of a few mountain snow showers and gusty northwest winds, the next impactful system looks to arrive late Fri into Fri night. THis system is yet another in a parade of clipper systems that have affected the area over the past few weeks. The main energy from this system won't be coming onshore until today, then tracking east along the northern tier of the U.S before diving SE across the Great Lakes into the Northeast and mid Atlantic region. There have been swings in the guidance the past few days with regards to the track, which will have large implications on snowfall amounts. Guidance has steadied on the more southern track across the mid Atlantic region, placing our area on the cold side of the storm with all snow expected.

Most sources of guidance indicating a fairly strong area of low level F-Gen to the north of the surface cyclone track, which would result in a swath of moderate/heavy snowfall. At this time, the blended guidance is placing this just south/west of our area, with light to moderate accumulation in our area from around I-90 south. The latest 24-hr NBM probs for > 2" are 50-75% and for > 4" are 30- 60% from the I-90 corridor south. Probs for > 6" are 30-50% limited to the E. Catskills. So this would be the area to watch for possible 6-7" amounts. Will continue to monitor trends.

KEY MESSAGE 4...

The next system already starts to approach on Sun, as a stronger/progressive upper low moves into Great Lakes, with the parent surface cyclone forecast to track east across Quebec/Ontario Sun into Mon. Most ensemble guidance is in good agreement with a northerly storm track, which would result in a warm front producing over-running precip with potential for low level cold air initially trapped at the surface. Based on this pattern, there is the potential for a wintry mix (including snow, sleet and/or freezing rain), especially affecting the higher terrain and areas north of Albany. Precip could end as rain ahead of the system's cold front sometime late Sun into Sun night, most favored in lower elevations. 48-hr NBM probs for > 0.50" liquid equivalent are 50-70% across the area. Conditions then turn colder and windier behind this system for early next week.

AVIATION /06Z WEDNESDAY THROUGH SUNDAY/

Low pressure continues to move east of New England this morning with lingering IFR/MVFR conditions from KALB/KPSF northward with some LIFR cigs near KGFL with patchy drizzle and light snow. KPOU is VFR, but MVFR cigs may briefly return before the winds increase in the wake of the cyclone and cold front between 07Z-09Z/Wed. Cigs/vsbys will rise to MVFR/VFR levels between 09Z-12Z/Wed, as cigs will range from 2-4 kft AGL. The cigs will continue to rise to VFR levels between 15Z-18Z/WED with bases 3.5-5 kft AGL and expect some clearing by 21Z/WED. Some high clouds will increase shortly before or just after 00Z/Thu.

The winds will be southeast/south at 5-10 KT early this morning, then veer to the southwest to west at 10-15 KT with some gusts 20-25 KT by 09Z/WED. The winds will further veer to the northwest/north at 10-20 KT with gusts 25-35 KT after 12Z/Wed and then will gradually decrease in the mid to late pm from the N/NW at 10 KT or less and then become light and variable at 5 KT or less after 00Z/THU.

LLWS will continue to be an issue at KPSF prior to 09Z/WED with the 2 kft winds northwest around 40 KT and the sfc winds 10 KT or less. Deeper mixing will occur after 09Z/Wed and LLWS will diminish at KPSF.

Outlook...

Thursday Night: Low Operational Impact. Breezy. NO SIG WX. Friday: Low Operational Impact. Slight Chance of SN. Friday Night: High Operational Impact. Definite SN. Saturday: Moderate Operational Impact. Chance of SN. Saturday Night: Low Operational Impact. Slight Chance of SN. Sunday: High Operational Impact. Likely RA...SN...FZRA...SLEET.

ALY WATCHES/WARNINGS/ADVISORIES

CT...None. NY...Wind Advisory until noon EST today for NYZ038>040-047>054- 058>061. Winter Weather Advisory until 7 AM EST this morning for NYZ032- 033-038-039-082. MA...Wind Advisory until noon EST today for MAZ001-025. VT...Winter Weather Advisory until 7 AM EST this morning for VTZ013- 014.